Chelsea signed Christian Pulisic in January but loaned him back to Dortmund.
The USA international was presented with yellow flowers on the Westfalenstadion pitch minutes before kick-off in the Bundesliga match with Fortuna Dusseldorf on Saturday afternoon.
“Dortmund will always feel like home for me,” Pulisic told supporters, who gave him a warm round of applause, according to Daily Mail.
Pulisic said his goodbye in style to the Dortmund fans by scoring against Fortuna Dusseldorf, his fourth league goal of the season.
“It’s a privilege to have signed for such a legendary club,” said Pulisic back in January after his £58million switch to London had been confirmed.